Biogeochemical responses to climate variability
Project Manager: Tim Pennington/Reiko Michisaki
Lead Scientist: Francisco Chavez

With current and emerging technologies we have opened a window to the dynamic connections between physical, chemical and biological processes in central California waters. Our explorations have uncovered the drivers of seasonal and interannual variations in the main biogeochemical cycles of Monterey Bay. As our understanding improves the ocean becomes a natural laboratory in which we can study processes general to both coastal and open ocean systems. Here we propose to continue this exploration of central California waters for three more years. Our long-term objective is to develop a state-of-the-art ocean observing system that will take the pulse of the central California ecosystem continuously, with minimal human intervention.

Our short-term objectives are to:

1. Continue the shipboard time series to C1, M1 and M2 and moorings M1, M2 and S2. We have tantalizing indications that a regime shift may have occurred towards the end of the last decade. The next several years will be critical in confirming this shift. And of course the shadow of global warming looms; the data collected to date provides the baseline needed to assess the impact of anthropogenic perturbations.
2. Initiate an Autonomous Underwater Vehicle (AUV) section parallel to the shipboard effort to determine the aliasing in the ship measurements and the feasibility of regular AUV surveys. A separate proposal detailing the development of an AUV payload is being put forth.
3. Continue collaborations with our colleagues working on midwater and benthic systems to gain a better understanding of the fate of surface primary production.
4. Continue the synthesis of data collected to date. Emphasis will be on the development of conceptual models that can be tested experimentally and specific equations for modeling and prediction. In addition new nuggets are continually mined out of the existing archives.
5. Continue comparison of new and existing data collected from ships and moorings to determine which measurements can be made long term from unattended platforms.
6. Develop algorithms that relate autonomous measurements (i.e. fluorescence, backscatter, attenuation) to ship-based measurements such as primary production.
7. Use measurements of currents to predict trajectories for phytoplankton, larval stages of benthic invertebrates and other zooplankton.
8. Support canyon dynamics with repeated CTDs at site C1 for calibration of in situ sensors.
9. Provide data for model initialization and validation. Analyze model solutions to determine if our first principles can be used to simulate the real world. Develop new first principles and use models to carry out experiments that will help define future ocean observing systems.

Every policy document written over the past decade emphasizes the need for sustained time-series measurements to characterize natural and human-induced changes in ocean processes. While many coastal efforts exist, few have been able to sustain time series like those at Hawaii and Bermuda for open ocean sites. The MBARI time series is unique in this respect. The MBARI effort is multi-investigator including Chavez, DeLong, Friederich, Johnson, Scholin, and Silver. The data also support the research efforts of Robison, Barry and Paull as well as a large number of students and investigators from local institutions.